Hi I have a columbus 2 tone movement I want to service can someone advise me if these 2 tone movements are OK to put through an ultra sonic cleaner without removing the gold layering and if so for how long

I don't ultrasonic movement parts since I don't do repairs on movements but I do ultrasonic cases and dials. Normally I do initial cleaning for the heavy crud with a soft bristle tooth brush and dish soap or equiv.
I normally do 2-4 minutes and have yet to wipe out a dial or damage a case. I don't do too many more minutes than that on a dial since some tend to have cracks and past damage but so far I have not lost any chunks or made any damage worse by going this route.

I have done a few dials came up good I had old unwanted dial lot of hairline put it in cleaner to see how much punishment it would handle left it in for about 10 minutes with heat on full dial handled it OK except solder crumbled and was able to push out seconds sub dial at least I now know how to remove a sub dial when I need one for a replacement

Hi Jeff , I am not the expert on this area , I would just use a good cleaner , L&R or similar . The loss of the tu tone cuts the value greatly.

Thanks I agree once you've lost that finish you can't put it back not worth taking a chance